Improvement in tube-welding mandrels



A. TELFER. Tube-Welding Mandrel.

N. 214,535. Patented April22,1879.Y

g ggf( (l/frn ey- N4 PETERS. PHOTO-LITHOGRAPHER. WASMINGTbN. D C.

UNITED STATESPATENT OFFICE'1 ANDREW TELFER, OF BOSTON, MASSACHUSETTS.

IMPROVEMENT IN TUBE-WELDING MANDRELS.

Specification forming part of Letters Patent No. 214,535, dated April '22, 1879; applica-tion filed July 10, 1876. i

`1'0 att whom it may concern:

Be it known that I, ANDREW TELFER, of Boston, in the county of Suffolk and State of Massachusetts, h ave invented certain Im provements in Tube-W'elding Mandrels, of which` the following is a speciiication. Y

Figure l of the accompanying drawings is a central vertical longitudinal section, and' Fig. 2 is a front view of my improved weld` ing ball or mandrel.

`This invention -relates to certain new and useful improvements in so-called welding balls 7 or mandrels,7 used in the manufacture of lap-welded tubi1ig-pipes,lues, Sto. The object of these improvements is principally to lighten the weight ot' the metal and diminish the expense of the ball, to promote its durability, as well as to provide a means of obviatin g the objections heretofore caused by the gathering of dirt, slag, and other impurities of the iron ahead of the ball in the process of welding the tubing, Ste.

My invention consists mainly in forming apertures of a triangular or any desired shape through the shell of the head of a welding ball or mandrel, and in formin glongitudinal grooves in the outer periphery of the body of the ball or c mandrel, so as to lighten theweight ofthe metal and allow the passage of the dirt, slag, and

'other impurities of the iron to the interior The exterior periphery ot' the body of the ball or mandrel is formed with longitudinal grooves E.

Ordinarily, when the tubing or pipe, Smc., passes over the ball or mandrel in the process of welding, the dirt, slag, and other impuri ties of the tubing, &c., collect ahead of the ball and obstruct the ready passage of the tubing; butin myimprovelnents the dirt, slag, 85e., fall through the apertures D and collect within the ball, from which they are readily removed after the welding process, and are also carried along the grooves E to the rear of vthe ball, thus allowing the free passage ofthe tube.

By perforating the ball-head C, as above Y described, the ball is rendered more durable by not h'a\fing to overcome the friction heretofore occasioned by the collection of the dirt, Src., ahead of it. Moreover, it is rendered less expensive by diminishing the weight of metal employed in its construction.

Having thus fully described my improvements, what I claim as my invention, and desire to secure by Letters Patent, is-

l. A welding ball or mandrel having its head perforated with triangular or other shaped apertures D, substantially as specified.

'2. The combination, with a welding ball or Vmandrel having its head perforated with triangular or other shaped apertures, of the lon gitudinal grooves E, substantially as speciiied.

In testimony that I claim the foregoing as my own invention l affix my signature in presence of two witnesses.

ANDREW ritratta.A

Witnesses.:

A. F. KooNs, I-I. S. HART. 

